Forficula auricularia

Linnaeus, 1758

European earwig, common earwig

is an to Europe, western Asia, and North Africa, now across North America, Australia, and New Zealand. It is recognized by -like —curved in males, straight in females—and concealed that unfold to resemble human ears, inspiring both its and specific epithet. The exhibits extended maternal care, with females guarding and in underground nests. vary geographically: temperate typically produce one annually, while warmer regions may support two broods.

Forficula auricularia by (c) Katja Schulz, some rights reserved (CC BY). Used under a CC-BY license.Forficula auricularia by (c) Judy Gallagher, some rights reserved (CC BY). Used under a CC-BY license.Forficula auricularia01 by wikipedia. Used under a Attribution license.

Pronunciation

How to pronounce Forficula auricularia: /fɔrˈfɪk.jʊ.lə ɔːˌrɪk.jʊˈlɛə.rɪə/

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

Distinguished from other by: (1) second tarsal lobed and extending below third segment; (2) male strongly curved with broadening and versus straight female cerci; (3) 11–14 segmented ; (4) chemistry (2-methyl-1,4-benzoquinone). In North America, distinguished from earwigs by its larger size and more male . Note: F. auricularia is now recognized as a including F. dentata, F. mediterranea, and F. aeolica, which are morphologically indistinguishable but genetically distinct and reproductively isolated.

Images

Appearance

Reddish-, flattened elongated body approximately 12–15 mm long. Shield-shaped covers the . Two pairs of : hardened () protect delicate, fan-shaped that fold beneath. slender, 11–14 segmented. Prominent () at tip—large, curved, and in males with ; straight, slender, and less robust in females, approximately 3 mm long. Second tarsal lobed, extending distally below third segment. resemble but lighter in color with reduced or absent wings.

Habitat

Cool, moist microhabitats with mean temperatures around 24°C. Occupies soil crevices, bark cracks, mulch, hollow flower stems, and protected parts such as dried curled leaves. In agricultural settings, shelters under trunk wraps and cardboard guards on young trees. Prefers well-drained slopes, southern exposures to avoid excessive moisture. Aggregates in dark, humid daytime shelters at of 50–100 individuals per square meter. Hibernates approximately 5 mm below soil surface.

Distribution

to Europe, western Asia, and North Africa. to North America (early 20th century, now widespread except far southeastern states), New Zealand (European settlers), and Australia (present >170 years, expanding in grain-growing regions). Occurs in temperate to semi-arid climates with high winter rainfall and pronounced temperature seasonality. Human influence strongly correlates with distribution limits in invaded ranges.

Seasonality

Primarily year-round. In temperate regions: active May–November in tree shelters; immatures October–June in ground shelters. One annually in cold continental climates; two broods in warmer regions. Mating peaks August–September. occurs in adult or nymphal stages depending on climate. Mediterranean show different with hibernating rather than adults.

Diet

, functioning as and scavenger. Consumes living and dead material (flowers, green foliage, seedlings, soft fruits), small (, , insect ), and dead insects. Documented feeding on: common hedge mustard (Sisymbrium officinale), clover (Trifolium repens), dahlia (Dahlia variabilis), molasses, lichens, . Prefers meat or sugar to natural plant material when available. consume more insects than ; nymphs feed more heavily on plant material. Practices , consuming maternal and sibling .

Host Associations

Life Cycle

development with four nymphal . Females lay ~50 pale to cream-colored elliptical in underground autumn nests. Extended maternal care: female guards eggs, cleans them with mouthparts and to remove fungal spores, applies cuticular hydrocarbons for chemical protection, and relocates clutch under stress. Eggs hatch in spring; mother continues care through first instar, providing protection, , food, and temperature regulation. remain in nest until after first moult, then accompany mother on foraging excursions. maintained through maternal care period (~1 month to maturity). Two distinct phases: nesting phase (family units with maternal care) and free-foraging phase (nymphs independent, may produce second in favorable conditions).

Behavior

forager, shelter-seeker. Aggregates in groups of 50–100 individuals per square meter using (2-methyl-1,4-benzoquinone/toluquinone from and tibial glands), with stage-specific components attracting different age . Courtship involves mutual tactile stimulation: males wave or bob , stroke and encircle female body with ; females respond with arching, bobbing, twisting. Copulation occurs with male and female facing opposite directions, surfaces in contact, pairs remaining joined for hours. Females feed during copulation. occurs through three mechanisms: inter- dispersal by females, nymphal dispersal associated with heightened locomotory activity (

Ecological Role

contributing to of agricultural pests, particularly in orchards. Documented suppression of woolly apple aphid and green apple aphid . Also functions as and scavenger. facilitates transfer of bacteria and serves as food source. possess antimicrobial properties protecting nest from . In high , can become pest causing damage to seedlings, soft fruits, flowers, and corn . influenced by climate suitability and human activity.

Human Relevance

Agricultural impact: pest of seedlings, soft fruits (, raspberries, blackberries, stone fruits), sweet corn (), flowers (dahlias, zinnias, marigolds, carnations, roses), and potentially citrus; also agent reducing in orchards. Household pest in North America, invading crevices and consuming pantry foods. Control methods include ( Triarthria setipennis, Ocytata pallipes; fly Bigonicheta spinipenni; Erynia forficulae, anisopliae; nematode Mermis nigrescens; birds), physical traps (rolled newspaper, bamboo tubes, wooden boards, ), and (diazinon, ). Subject to / development in conventional orchards. Research model for maternal care, , and sociality studies.

Similar Taxa

  • Forficula dentataPart of F. auricularia ; morphologically indistinguishable, reproductively isolated, distinguished by mitochondrial and geographic distribution (British Isles, Western Europe, warmer climates with two )
  • Forficula mediterraneaPart of F. auricularia ; morphologically indistinguishable, genetically distinct member
  • Forficula aeolicaPart of F. auricularia ; morphologically indistinguishable, genetically distinct member
  • Forficula pubescensCo-occurs in Mediterranean apple orchards; distinguished by year-round presence and different ( April–June)
  • Native North American earwigsGenerally smaller with less male than F. auricularia

Misconceptions

Name '' and urban legend of crawling into human ears derive from resemblance of unfolded to human ears, not actual . While two documented cases of earwigs entering human ears exist, this is extremely rare and not representative behavior. used for defense, courtship, and capture—not aggressive clasping during copulation. Often incorrectly blamed for apple damage; field studies show no correlation between earwig and fruit damage, with earwigs typically sheltering in pre-existing damage rather than causing it.

More Details

Aggregation Pheromone

Produces 2-methyl-1,4-benzoquinone (toluquinone) from tibial glands and ; attracts all developmental stages with stage-specific components (benzoquinones attract but not ). via olfaction, not contact chemoreception.

Insecticide Resistance

in conventional orchards show developed to (chlorpyriphos-ethyl) through elevated glutathione-S-transferase and carboxylesterase activity, plus reduced sensitivity. Females more than males. Associated costs: smaller body size in conventional orchard populations.

Genomic Resources

High-quality assembly available (1.06 Gb, 31.03% GC, N50 12.55 Mb, 12,876 -coding genes); isolate belongs to B of two known genetic subspecies.

Altruistic Maternal Behavior

Females apply -specific cuticular hydrocarbon bouquets to enabling kin recognition, yet do not reject foreign eggs and provide equivalent care—demonstrating without kin .

Tags

Sources and further reading